Forest Restoration Carbon Analysis of Baseline Carbon Emissions and Removal in Tropical Rainforest at La Selva Central, Peru

Abstract

Conversion of tropical forest to agricultural land and pasture has reduced forest extent and the provision of ecosystem services, including watershed protection, biodiversity conservation, and carbon sequestration. Forest conservation and reforestation can restore those ecosystem services. We have assessed forest species patterns, quantified deforestation and reforestation rates, and projected future baseline carbon emissions and removal in Amazon tropical rainforest at La Selva Central, Peru. The research area is a 4800 km 2 buffer zone around the Parque Nacional Yanachaga-Chemillén, Bosque de Protección San Matías-San Carlos, and the Reserva Comunal Yanesha. A planned project for the period 2006-2035 would conserve 4000 ha of forest in a proposed 7000 ha Área de Conservación Municipale de Chontabamba and establish 5600 ha of natural regeneration and 1400 ha of native species plantations, laid out in fajas de enriquecimiento (contour plantings), to reforest 7000 ha of agricultural land. Forest inventories of seven sites covering 22.6 ha in primary forest and 17 sites covering 16.5 ha in secondary forest measured 17 073 trees of diameter ≥ 10 cm. The 24 sites host trees of 512 species, 267 genera, and 69 families. We could not identify the family of 7% of the trees or the scientific species of 21% of the trees. Species richness is 346 in primary forest and 257 in the secondary forest. In primary forest, 90% of aboveground biomass resides in old-growth species. Conversely, in secondary forest, 66% of aboveground biomass rests in successional species. The density of trees of diameter ≥ 10 cm is 366 trees ha -1 in primary forest and 533 trees ha -1 in secondary forest, although the average diameter is 24 ± 15 cm in primary forest and 17 ± 8 cm in secondary forest. Using Amazon forest biomass equations and wood densities for 117 species, aboveground biomass is 240 ± 30 t ha -1 in the primary sites and 90 ± 10 t ha -1 in the secondary sites. Aboveground carbon density is 120 ± 15 t ha -1 in primary forest and 40 ± 5 t ha -1 in secondary forest. Forest stands in the secondary forest sites range in age from 10 to 42 y. Growth in biomass (t ha -1 ) as a function of time (y) follows the relation: biomass = 4.09 -0.017 age 2 (p < 0.001). Aboveground biomass and forest species richness are positively correlated (r 2 = 0.59, p < 0.001). Analyses of Landsat data show that the land cover of the 3700 km 2 of non-cloud areas in 1999 was: closed forest 78%; open forest 12%, low vegetation cover 4%, sparse vegetation cover 6%. Deforestation from 1987 to 1999 claimed a net 200 km 2 of forest, proceeding at a rate of 0.005 y -1